Wheel Travel Question

[goathearder]

Hey All,
I have a dumb wheel travel question but I have never had to calculate it before so I just want to make sure.

I broke a shock mount off the front axle two weekends ago off-roading when I hit an unexpected jump and came down pretty hard. Seeing as the shock mount shouldn't really see a ton of stress, I think I bottomed it out.

As I was in there welding the shock mount back on, I noticed that I have about 6 inches between the bumpstops and the spring pad/axle and only about 3.5 inches of up travel on the shock at ride height.

I am assuming that the travel available to the shock needs to be more than the travel to the bumpstop so either I have the wrong shocks, need longer bumpstops or both.

Can anyone tell me if I am thinking about this correctly?

Thanks,
John

 

[4X4HIGH]

You are half correct, the bumpstop is there so the shock can't bottom out but more importantly so the springs don't go reverse arch. The stock front shock mounts are very notorious for breaking (broke mine about 3 times already and then got tired of them breaking so I built some new ones as the old ones were done after 3 times of welding them back together (break in different places each time).

 

[owenst7]

Your bumpstops are located on the frame with the design of an inverted (reverse curve/stock) spring. Yes, your bumpstops are there to keep uptravel from causing damage to oil pans, springs, shocks, etc. Assuming you have positive arch springs, your bumpstops aren't going to be doing there job.

You need to change your bumpstop system around if you're going to be jumping the truck lol. I personally don't think that extending them down from the stock location is the best solution...Under abuse I can see them tearing up the frame rail with the way they're mounted stock if you add a big lever arm to them.

It would be fine if you just found thicker bumpstops, they aren't going to transfer bending stress to the mount very effectively, but those big bumpstops get spendy. I just don't think the common square tube spacer is the best permanent solution under heavy abuse.

 

[goathearder]

Well, I don't plan on jumping the truck, it was quite an accident the first time, hahahahahahaha. I do want to make sure that I don't mess up the shocks though.

Do you guys think its possible the PO put on the wrong shocks and they just don't have enough uptravel?

When I bought it he told me it was a 6 inch lift with a 3 inch body but I measured the lift pucks and they are only 2 inches and the blocks in the rear are 4 inches so I don't think he really knew anything about the suspension and he probably could have put the wrong stuff on it.

 

[owenst7]

Well, I don't plan on jumping the truck, it was quite an accident the first time, hahahahahahaha. I do want to make sure that I don't mess up the shocks though.

Do you guys think its possible the PO put on the wrong shocks and they just don't have enough uptravel?

When I bought it he told me it was a 6 inch lift with a 3 inch body but I measured the lift pucks and they are only 2 inches and the blocks in the rear are 4 inches so I don't think he really knew anything about the suspension and he probably could have put the wrong stuff on it.

Probably, but the bumpstops need to be there no matter what shocks are there. The springs shouldn't be able to reverse curve, or flatten beyond flat under compression or it will eventually damage them.

Lots of us around here don't follow these rules like we should, but it will make your springs last and done correctly it will make the truck more stable too when your flexed out.

 

[goathearder]

Yea, I definitely don't want to remove the bumpstops, I want to make sure they are working properly so I don't damage my shocks.

Is the only way to measure compressed and extended shock lengths to take the shocks off and run the truck up an RTI ramp?

 

[owenst7]

Yea, I definitely don't want to remove the bumpstops, I want to make sure they are working properly so I don't damage my shocks.

Is the only way to measure compressed and extended shock lengths to take the shocks off and run the truck up an RTI ramp?

You can flex it out with a jack.

The bumpstops need to hit when the spring flattens. That's their job. If the shocks bottom out first, you can make the bumpstops lower but you sacrifice uptravel that way. You can just look at the way the suspension moves and gauge that shock length within a quarter inch or so. Just make a straight-line across the eyes of the spring and that's roughly how much vertical travel you should have before hitting the bumpstops.